Rotational atherectomy device with distal embolic protection

ABSTRACT

A rotational atherectomy device for removing a stenotic tissue from the iliac artery of a patient. The device comprises a flexible, rotatable drive shaft having an elongated proximal portion, an elongated distal portion, and an abrasive element mounted to the drive shaft between the elongated proximal and distal portions of the drive shaft and configured for rapid rotation together with the drive shaft.

The present invention relates to a rotational atherectomy device forremoving a stenotic lesion from within a vessel of a patient. Morespecifically, the invention relates to a rotational atherectomy devicefor removing or reducing a stenotic lesion in the iliac artery byrotating an abrasive element within the artery to partially orcompletely ablate the stenotic lesion and simultaneously remove out ofthe patient's body abraded particles (embolic particles or debris)released into the treated artery during the rotational atherectomyprocedure. It should be understood that rotational atherectomy devicesand rotational atherectomy procedures are often referred to asrotational angioplasty devices and rotational angioplasty procedures.One type of rotational atherectomy devices is referred to as an orbitalatherectomy device. All these terms may be used interchangeably herein.

Atherosclerosis, the clogging of arteries, is a leading cause ofcoronary heart disease. Blood flow through the peripheral arteries(e.g., carotid, femoral, renal, etc.), is similarly affected by thedevelopment of atherosclerotic blockages. One conventional method ofremoving or reducing blockages in blood vessels is known as rotationalatherectomy. A device and a method for performing the RotationalAtherectomy Procedure are known from U.S. Pat. No. 4,990,134 to Auth. Arotational atherectomy (angioplasty) device based on this patent iscommercially available from Boston Scientific Corporation of Natik,Mass., USA. The Auth device includes an abrasive burr which is attachedto a distal end of a hollow flexible drive shaft. The abrasive surfaceof the burr is formed from diamond particles. The device is rotatedaround a special guidewire, which is advanced across the stenoticlesion. The device is advanced towards the stenotic lesion around (over)the guidewire. The abrasive burr is positioned against the occlusion andthe drive shaft is rotated around the guidewire at extremely high speeds(e.g., 20,000-160,000 rpm). As the abrasive burr rotates, the physicianrepeatedly advances it towards the stenotic lesion so that the abrasivesurface of the burr scrapes against the occluding tissue anddisintegrates it, reducing the occlusion and improving the blood flowthrough the vessel. It should be understood that the terms abrasive burrand abrasive element may be used interchangeably herein.

U.S. Pat. No. 6,132,444 to Shturman (the instant inventor) et al.,describes another rotational atherectomy device of the prior art. TheShturman device comprises an abrasive element located proximal to andspaced away from a distal end of the drive shaft. This abrasive elementis formed from diamond particles directly electroplated to wire turns ofan enlarged diameter portion of the drive shaft. The enlarged diameterportion of the drive shaft is asymmetric and is responsible forproviding an abrasive element with a centre of mass which is spaced awayfrom the rotational axis of the drive shaft. The device is rotatedaround a special guidewire and its eccentric abrasive element is able toopen the treated stenotic lesion to a diameter substantially larger thanthe maximum diameter of the abrasive element.

U.S. Pat. No. 7,507,245 to Shturman (the instant inventor) et al.,describes a third embodiment of the rotational atherectomy device of theprior art. The device of U.S. Pat. No. 7,507,245 is similar to thedevice of U.S. Pat. No. 6,132,444 except that the abrasive elementcomprises a prefabricated abrasive crown disposed around the eccentricenlarged diameter portion of the drive shaft. The device is commerciallyproduced by Cardiovascular Systems, Inc. of St. Paul, Minn.

The Patent Application WO 2006/126176 to Shturman (the current inventor)describes a rotational atherectomy device comprising a solid eccentricabrasive element and two solid asymmetric support elements mounted on ahollow flexible drive shaft. The solid asymmetric support elements havetheir centres of mass spaced away (offset) from a rotational(longitudinal) axis of the drive shaft and, during rotation of the driveshaft, act as counterweights to the eccentric abrasive element. In themost preferred embodiment of the invention, the centre of mass of eachof the solid counterweights is separated from the centre of mass of theabrasive element by an angle of 180 degrees around the axis of the driveshaft. When the drive shaft of the rotational atherectomy device withsolid counterweights is rotated, centrifugal forces generated by thesolid counterweights and the eccentric abrasive element preferably actin substantially the same plane but in opposite directions. Thesecentrifugal forces cause the distal end portion of the drive shaft toflex and assume a generally bowed or arcuate shape. During rotation ofthe drive shaft, the abrasive element and each of two solidcounterweights move in orbital fashions around the axis of rotation ofthe drive shaft in orbits that are substantially larger than therespective diameters of the abrasive element or solid counterweights.

Disadvantages associated with either limited or completely absent distalembolic protection of all commercially available rotational atherectomydevices have been addressed in WO 2006/126076 to Shturman (the instantinventor). In accordance with WO 2006/126076 drive shaft has a fluidimpermeable wall and allows an antegrade flow of pressurised fluidthrough a lumen of the drive shaft from a proximal end towards a distalend of the drive shaft. A portion of the pressurised fluid, afterentering the treated vessel distal to the abrasive element, flows in aretrograde direction around the abrasive element and across the treatedstenotic lesion to entrain abraded embolic particles and evacuate themfrom the treated vessel as soon as they have been abraded by theabrasive element of the device. Several other embodiments of the devicewith distal embolic protection capability are disclosed in WO2008/006704, WO 2008/006705, WO 2008/006706, WO 2008/006708, and WO2008/062069 to Shturman (the instant inventor), but in every one ofthese embodiments the abraded particles are entrained and evacuated fromthe patient's body by fluid which flows around the abrasive element inthe retrograde direction (i.e. against the direction of the flow ofblood in the treated artery).

Over the last few years Edwards Lifesciences Corp. and CoreValve, Inc.(both of Irvine, Calif.) introduced to the market and clinical trialsrespectfully two types of novel Aortic Heart Valves which are configuredfor Transcatheter Aortic Valve Replacement. A delivery catheter fortransfemoral placement of Edwards SAPIEN Heart Valve has an outerdiameter of about 7 millimeters. The Delivery Catheter which is usedduring the CoreValve ReValving® percutaneous aortic valve replacementprocedure has an outer diameter of about 6 millimeters. The deliverycatheters of both companies have to be advanced though the Iliac Arteryof the patient. A large number of patients who may benefit from theTranscatheter Aortic Valve Replacement have atherosclerotic occlusionsin their Iliac Arteries. Often Iliac Arteries of older patients are notonly affected by calcified atherosclerotic lesions but are tortuous aswell. Therefore what is needed is a rotational atherectomy device whichwill be able to partially or completely ablate both the soft andcalcified stenotic lesions in the tortuous iliac arteries of olderpatients.

It is the objective of this invention to provide a rotational (orbital)atherectomy device which can ablate atherosclerotic plaques in tortuousiliac arteries and simultaneously remove abraded particles out of thepatient's body.

It is another objective of this invention to provide a rotational(orbital) atherectomy device which not only can simultaneously ablatethe plaque and remove abraded particles out of the patient, but whichcan remove abraded particles from the iliac artery without the need toform the retrograde flow of fluid around the abrasive element of thedevice.

All rotational (orbital) atherectomy devices described above have anabrasive element which is moved back and forth across the stenoticlesion by alternately pulling and pushing on the elongated drive shaftof the device. Pushing on the proximal end of the elongated drive shaft,after removing the guidewire, may cause the flexible drive shaft to bendwithin the elongated drive shaft sheath. This, in turn, may causediscrepancy between the forward movement of the turbine (the drive shaftis connected to the turbine) and the forward movement of the abrasiveelement. Therefore, it is yet another objective of this invention toeliminate such a discrepancy by providing a rotational (orbital)atherectomy device in which the abrasive element is moved back and forthacross the stenotic lesion by alternately pulling one end of the driveshaft in one direction and the other end of the drive shaft in theopposite direction.

According to a preferred embodiment of the invention, the rotationalatherectomy device for removing a stenotic tissue from the iliac arteryof a patient is comprising a flexible, rotatable drive shaft having anelongated proximal portion, an elongated distal portion, and an abrasiveelement mounted to the drive shaft between the elongated proximal anddistal portions of the drive shaft and configured for rapid rotationtogether with the drive shaft, the drive shaft configured for extendingthroughout an entire length of the iliac artery to be treated and havingone elongated portion of the drive shaft extending out of the patientthrough a first access opening located in a femoral artery which isipsilateral to the treated artery, and the other elongated portion ofthe drive shaft extending through a second access opening located inanother peripheral artery of the patient.

Preferably, the device includes a pair of elongated drive shaft sheaths,one drive shaft sheath configured for slidably receiving the elongatedproximal portion of the drive shaft and the other drive shaft sheathconfigured for slidably receiving the elongated distal portion of thedrive shaft, the drive shaft sheaths having distal ends and beingconfigured for advancement around corresponding portions of the driveshaft into the treated iliac artery such that the distal ends of thesheaths become positioned spaced away from the abrasive element, thespace between the distal ends of the drive shaft sheaths allowing torepeatedly move the rotating abrasive element back and forth along thetreated iliac artery and abrade the stenotic lesion.

Preferably, one of the drive shaft sheaths should be in a fluidcommunication with a source of pressurized fluid, said pressurized fluidflows into the treated artery through said one drive shaft sheath,entrains abraded embolic particles, and is drained out from the treatedartery through the other drive shaft sheath.

Preferably, an inflatable occlusion balloon should be mounted to atleast one of the drive shaft sheaths, the inflatable occlusion balloonbeing configured, when inflated, to restrict the flow of fluids aroundthe sheath towards and away from the treated stenotic area.

Preferably, an inflatable occlusion balloon is mounted to at least oneof the drive shaft sheaths, the inflatable occlusion balloon beingmounted near the distal end of the sheath and configured, when inflated,to center the distal end of the drive shaft sheath in the treatedartery.

Preferably, an inflatable occlusion balloon should be mounted to each ofthe two drive shaft sheaths, the inflatable occlusion balloons beingmounted near the distal ends of the sheaths and configured, wheninflated, to center the distal ends of the drive shaft sheaths in thetreated artery.

Preferably, an inflatable occlusion balloon should be mounted to each ofthe two drive shaft sheaths, the inflatable occlusion balloons beingmounted near the distal ends of the sheaths and configured, wheninflated, to restrict the flow of fluids around the sheaths towards andaway from the treated stenotic area.

Preferably, each of the drive shaft sheaths should be caring aninflatable occlusion balloon, the occlusion balloons being mounted nearthe distal ends of the sheaths and configured, when inflated, torestrict the flow of fluids around the sheaths towards and away from thetreated stenotic area.

Preferably, each of the drive shaft sheaths should be caring aninflatable occlusion balloon, the occlusion balloons being mounted neatthe distal ends of the sheaths and configured, when inflated, to centerthe distal ends on the drive shaft sheaths in the treated artery.

Preferably, at least one of the elongated portions of the drive shaft isconfigured to be connected to a rotatable shaft of a prime mover, theprime mover being configured for rotating the drive shaft.

Preferably, the prime mover is slidably received within a housing of anadvancer mechanism so that an operator can alternately pull and push onthe elongated portion of the drive shaft by moving the prime mover backand forth within the housing of the advancer mechanism.

Preferably, the elongated distal portion of the drive shaft isconfigured to be connected to a rotatable shaft of a prime mover, theprime mover being configured for rotating the drive shaft.

Preferably, the prime mover is slidably received within a housing of anadvancer mechanism so that an operator can alternately pull and push onthe elongated distal portion of the drive shaft by moving the primemover back and forth within the housing of the advancer mechanism.

Preferably, the elongated proximal portion of the drive shaft isconfigured to be connected to a rotatable shaft of a prime mover, theprime mover being configured for rotating the drive shaft.

Preferably, the prime mover is slidably received within a housing of anadvancer mechanism so that an operator can alternately pull and push onthe elongated proximal portion of the drive shaft by moving the primemover back and forth within the housing of the advancer mechanism.

Preferably, the device includes a pair of prime movers and each of theelongated portions of the drive shaft is configured to be connected to arotatable shaft of one of the two prime movers, the prime movers beingconfigured for rotating the drive shaft.

Preferably, each of the prime movers is slidably received within ahousing of an advancer mechanism so that an operator can alternatelypull on distal and proximal portions of the drive shaft by alternatelymoving the prime movers away from distal ends of the housings of theadvancer mechanisms.

Preferably, proximal ends of both elongated portions of the drive shaftare configured for releasable connection to opposite ends of a rotatableshaft of a prime mover which is configured tor rotating the drive shaft.

Preferably, the prime mover is slidably received within a housing of anadvancer mechanism so that an operator can alternately pull on distaland proximal portions of the drive shaft by moving the prime mover backand forth within the housing of the advancer mechanism.

Preferably, the device includes a prime mover for rotating the driveshaft and an advancer mechanism which is configured for slidablycarrying the prime mover.

Preferably, one of the elongated portions of the drive shaft isconfigured to be connected to a rotatable shaft of the prime mover, andthe drive shaft sheath extending around said portion of the shaft isconfigured to be connected to a housing of the advancer mechanism sothat an operator can repeatedly move the abrasive element back and forthacross the stenotic lesion by moving the prime mover back and forth withrespect to the housing of the advancer mechanism.

Preferably, the atherectomy device comprises a pair of advancermechanisms, a first advancer mechanism having a first housing whichslidably carries a prime mover configured for rotating the drive shaft,and a second advancer mechanism having a second housing which slidablycarries a hollow body comprising a rotatable shaft supported by at leastone bearing which is disposed within the hollow body, and one of the twoelongated portions of the drive shaft is configured to be connected to arotatable shaft of the prime mover, and the other of the two elongatedportions of the drive shaft being configured to be connected to therotatable drive shaft of the second advancer mechanism, and the driveshaft sheaths are configured to be connected to distal ends of thehousings of the advancer mechanisms so that an operator can move theabrasive element across the stenotic lesion by alternately moving theprime mover and the hollow body away from the distal ends of thehousings of the first and second advancer mechanisms.

Preferably, the device comprising a flexible, rotatable drive shafthaving an elongated proximal portion, an elongated distal portion, andan abrasive element mounted to the drive shaft between the elongatedproximal and distal portions of the drive shaft and configured for rapidrotation together with the drive shaft, the drive shaft configured forextending throughout an entire length of the artery to be treated andhaving one elongated portion of the drive shaft extending out of thepatient through a first access opening located in a femoral artery, andthe other elongated portion of the drive shaft extending through asecond access opening located in another peripheral artery of thepatient.

Preferably, the device includes a pair of elongated drive shaft sheaths,one drive shaft sheath configured for slidably receiving the elongatedproximal portion of the drive shaft and the other drive shaft sheathconfigured for slidably receiving the elongated distal portion of thedrive shaft, the drive shaft sheaths having distal ends and beingconfigured for advancement around corresponding portions of the driveshaft into the treated artery such that the distal ends or the sheathsbecome positioned spaced away from the abrasive element, the spacebetween the distal ends of the drive shaft sheaths allowing torepeatedly move the rotating abrasive element back and forth along thetreated artery and abrade the stenotic lesion.

Preferably, one of the drive shaft sheaths is in a fluid communicationwith a source of pressurized fluid, said pressurized fluid flows intothe treated artery through said one drive shaft sheath, entrains abradedembolic particles, and is drained out from the treated artery throughthe other drive shaft sheath.

Preferably, the device includes a prime mover for rotating the driveshaft.

Preferably, the prime mover is slidably received within a housing of anadvancer mechanism so that an operator can repeatedly move the abrasiveelement back and forth across the stenotic lesion by repeatedly movingthe prime mover back and forth within the housing of the advancermechanism.

Preferably, the device includes an advancer mechanism which isconfigured for repeatedly moving the rotating prime mover together withthe rotating drive shaft and the abrasive element back and forth acrossthe treated stenotic lesion.

Preferably, the elongated drive shaft sheath which is selected fordraining fluid out of the treated artery should include a separatedrainage lumen which is configured exclusively for draining fluid andabraded particles out from the treated artery.

Preferably, the elongated drive shaft sheaths should include occlusionballoon inflation lumens.

Preferably, the abrasive element has a centre of mass which is spacesaway from the longitudinal axis of the drive shaft.

Preferably, each of the two elongated portions of the drive shaft is atleast 15 centimetres long.

Preferably, each of the two elongated portions of the drive shaft is atleast 30 centimetres long.

Preferably, an ultrasound transducer should be mounted near the distalend of one of the drive shaft sheaths, the ultrasound transducerallowing acquisition of transverse ultrasound images of the treatedartery.

Preferably, the second access opening should be located in a femoralartery which is contralateral with respect to the iliac artery to betreated.

Alternatively, the second access opening is located in an artery of theupper extremity of the patient.

The second access opening may be located in one of the radial arteriesof the patient.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a side sectional view of iliac arteries. A stenotic lesion tobe treated is located in the right iliac artery. A drive shaft of anatherectomy device of the invention is extending through the iliacarteries. FIG. 1 shows that an eccentric abrasive element is mounted tothe drive shaft between a pair of elongated portions of the drive shaft.FIG. 1 shows that one elongated portion of the drive shaft (i.e. distal)extends out of the patient through a first access opening located in theipsilateral to the lesion femoral artery of the patient and the otherelongated portion of the drive shaft (i.e. proximal) extends out of thepatient through a second access opening located in the contralateral tothe lesion femoral artery of the patient;

FIG. 2 is a side sectional view which shows that one elongated driveshaft sheath has been advanced over the elongate proximal portion of thedrive shaft, and another elongated drive shaft sheath has been advancedover the elongate distal portion of the drive shaft. FIG. 2 shows thatdistal ends of the sheaths are spaced away from the abrasive element.FIG. 2 shows occlusion balloons which are mounted to the sheaths neartheir distal ends. FIG. 2 shows that the elongated portion of the driveshaft on one side of the abrasive element (i.e. ipsilateral) has beenconnected to a turbine, and the corresponding elongated drive shaftsheath has been connected to an advancer mechanism. The advancermechanism slidably receives the turbine and allows moving the rotatingabrasive element back and forth across the stenotic lesion to betreated;

FIG. 3 is a side sectional view which shows that the elongated proximaldrive shaft sheath (i.e. on the contralateral side) has been connectedto a source of pressurized fluid. FIG. 3 illustrates that pressurizedfluid flows towards the treated iliac artery through the proximal driveshaft sheath and is drained from the artery through the distal driveshaft sheath. FIG. 3 illustrates that rotation of the drive shaft andits eccentric abrasive element has been initiated and that abradedparades are removed from the patient as soon as they are produced.

FIGS. 4 and 5 are side sectional views illustrating the process ofablation of the atherosclerotic plaque by the rotating abrasive elementwhich is repetitively moved back and forth across the stenotic lesion.FIGS. 4 and 5 show that the inflated occlusion balloons not onlyrestrict the flow of blood towards and away from the treated stenoticlesion but allow centering of the drive shaft within the treated arteryas well;

FIG. 6 is a side sectional view illustrating that a plurality ofultrasound transducers can be mounted to a distal end portion of one ofthe elongated drive shaft sheaths. These transducers allow repeatedlyacquiring cross-sectional ultrasound image(s) or the treated vesselthroughout the atherectomy procedure and enhancing its safety;

FIG. 6A is a cross-sectional view taken alone the line A-A shown in FIG.6 and shows an ultrasound image acquired by the ultrasound transducers;

FIGS. 7 through 9 are side sectional views showing that the elongatedportion on the drive shaft on each side of the abrasive element can beconnected to the advancer mechanism. This allows moving the abrasiveelement in one direction across the stenotic lesion by pulling on theelongated portion of the drive shaft located on one side of the abrasiveelement, and moving the abrasive element in the opposite direction bypulling on the elongated portion of the drive shaft located on the otherside of the abrasive element;

FIGS. 10 and 11 are side sectional views showing that proximal ends ofthe elongated portions of the drive shaft located on both sides of theabrasive element can be connected to the opposite ends of the sameturbine shaft. This allows moving the abrasive element back and forthacross the stenotic lesion by simultaneously pulling on one elongatedportion of the drive shaft and pushing on the other;

FIG. 12 is a side sectional view illustrating that after completing thetreatement of one iliac artery the abrasive element can be repositionedinto another iliac artery without removing the drive shaft out of thepatient's body;

FIG. 13 is a side sectional view illustrating that one elongated portionof the drive shaft (i.e. distal) extends out of the patient through afirst access opening located in the ipsilateral to the lesion femoralartery of the patient and the other elongated portion of the drive shaft(i.e. proximal) extends out of the patient through a second accessopening located in the radial artery of the patient;

Reference is made in this specification to the “distal” and “proximal”ends of the elongated drive shaft sheaths. For the purpose of thisspecification, the distal end is considered to refer to the end of thesheath which is located inside the patient's body, and the proximal endis considered to refer to that end of the sheath which is locatedoutside the patient's body. Embolic particles are indicated by symbol“EP”, and the flow of fluid through the device is indicated by arrows“F”. It should be noted that the terms “guidewire” and “guide wire” areused interchangeably in the medical device literature. The terms “primemover” and “gas turbine” are used interchangeably throughout thisspecification as well. It should be understood that any connection ofthe elongated portion of the drive shaft to a shaft of the prime movercan be made a releasable connection. It should be also understood thatany connection of the drive shaft sheath to a housing of an advancermechanism can be made a releasable connection.

Operation of the rotational atherectomy device to abrade the stenoticlesion located in the iliac artery will now be described with referenceto FIGS. 1 to 13 of the accompanying drawings.

FIG. 1 is a side sectional view of iliac arteries. A stenotic lesion 3to be treated is located in the right iliac artery 1. A drive shaft 10of an atherectomy device of the invention is extending through the iliacarteries. FIG. 1 shows that an eccentric abrasive element 16 is mountedto the drive shaft 10 between a pair of elongated portions of the driveshaft 11, 14. FIG. 1 shows that one elongated portion of the drive shaft(i.e. distal) 14 extends out of the patient through a first accessopening located in the ipsilateral to the lesion femoral artery 9 of thepatient and the other elongated portion of the drive shaft (i.e.proximal) extends out of the patient through a second access openinglocated in the contralateral to the lesion femoral artery 19 of thepatient. It should be understood that one of the of elongated portionsof the drive shaft 11, 14 may be shorter than the other, but even theshorter elongated portion of the drive shaft should have at least 15centimeters in its length. Preferably, each elongated portion of thedrive shaft should have at least 30 centimeters in its length.

It should be noted that the drive shaft 10 may be advanced into itsposition over the guidewire (not shown). The guide-wire may beintroduced, for example, from the contralateral side through apercutaneous puncture, and advanced superiorly towards the aorta 6. Aretrieval catheter (not shown) is introduced through a vascular accesssite in the ipsilateral femoral artery and advanced into the ipsilateraliliac artery. The retrieval catheter is used to grasp the guidewire andretract it interiorly through the ipsilateral vascular access site. Theabove described technique of advancing the guidewire is well known tothe interventional cardiologists and interventional radiologists. Theguidewire is removed after the drive shaft 10 has been advanced over it.

FIG. 2 is a side sectional view which shows that one elongated driveshaft sheath 41 has been advanced over the elongate proximal portion 11of the drive shaft 10, and another elongated drive shaft sheath 43 hasbeen advanced over the elongate distal portion 14 of the drive shaft 10.The elongated drive shaft sheaths 41, 43 are configured for slidablyreceiving corresponding portions of the drive shaft 10. FIG. 2 showsthat the distal ends of the sheaths 41, 43 are spaced away from theabrasive element 16. The space between the distal ends of the elongatedsheaths 41, 43 allows moving the rotating abrasive element 16 back andforth along the treated stenotic lesion 3 in the iliac artery 1. FIG. 2shows that the elongated distal portion 14 of the drive shaft 10 hasbeen connected to a prime mover 21 and the corresponding elongated driveshaft sheath 43 has been connected to a housing 23 of an advancermechanism 80 which carries the prime mover (i.e. gas turbine) 21. Theprime mover 21 is configured for rotating the drive shaft 10. Theadvancer mechanism 80 slidably receives the prime mover 21 within itshousing 23 and allows moving the rotating drive shaft 10 and itsabrasive element back and forth across the stenotic lesion to betreated. It should be noted that the prime mover 21 usually includes agas turbine, but it may be comprised from an electric motor as well.FIG. 2 shows that the proximal drive shaft sheath 41 has a femaleportion of the Luer Connector 47 near its proximal end. The LuerConnector 47 is configured for connecting the proximal drive shaftsheath 41 to a source of pressurized fluid.

FIG. 3 is a side sectional view which shows that the elongated proximaldrive shaft sheath 41 has been connected to a source of pressurizedfluid. FIG. 3 illustrates that pressurized fluid flows towards thetreated iliac artery 1 through the proximal drive shaft sheath 41 and isdrained from the artery through the elongated distal drive shaft sheath43 and its side branch 45. The direction of the flow of pressurizedfluid is indicated by arrows “F”. FIG. 3 illustrates that the elongatedproximal drive shaft sheath 41 is connected to a bag 49 with the salinesolution via a roller pump 48. It should be noted that a power injectoror any other suitable pump may be used for pumping fluid into theelongated proximal drive shaft sheath 41. FIG. 3 illustrates thatocclusion balloons 51, 53 have been inflated within the treated vessel1. The occlusion balloons 51, 53 are mounted to the elongated driveshaft sheath 41, 43 near the distal ends of the sheaths. The occlusionballoons 51 and 53, when inflated, not only restrict the flow of bloodtowards and away from the treated stenotic lesion 3 but allow centeringof the drive shaft within the treated artery 1 as well. FIG. 3 showsthat rotation of the eccentric abrasive element 16 has been initiated,and centrifugal force caused bowing of that portion of the drive shaft10 which extends between the distal ends of the elongated drive shaftsheaths 41, 43. It show be noted that the rotating drive shaft iscentered along a longitudinal axis of the iliac artery 1 at the distalends of the sheaths 41, 43 by inflated occlusion balloons 51, 53. Theabrasive element 16 is orbiting within the stenotic lesion and abradingit. The weight of the abrasive element 16, its eccentricity, androtational speed of the turbine define the centrifugal force which isbending the drive shaft and presses the abrasive element 16 against thestenotic tissue 3. It should be noted the potential diameter of theorbit of the eccentric abrasive element become increased when thedistance between the distal ends of sheaths is enlarged. FIG. 3illustrates that abraded particles “EP” are entrained by the flow offluid and they are removed from the treated iliac artery 1 and thepatient's body as soon as they are produced.

FIGS. 4 and 5 illustrated back and forth movements of the rotatingabrasive element along the treated iliac artery 1 and across thestenotic lesion 3. A physician can repeatedly move the rotating abrasiveelement back and forth by repeatedly moving back and forth the turbine21 (knob 25) within the housing 23 of the advancer mechanism 80.

FIG. 6 illustrates that a plurality of ultrasound transducers 60 can bemounted to a distal end portion of the elongated proximal drive shaftsheath 41. These transducers 60 allow repeatedly acquiringcross-sectional ultrasound image(s) of the treated vessel throughout theatherectomy procedure and enhancing its safety. FIG. 6A is across-sectional view taken along the line A-A shown in FIG. 6 and showsan ultrasound image acquired by the ultrasound transducers 60.

FIGS. 4 and 5 described above illustrated that repeated back and forthmovements of the rotating abrasive element 16 along the treated iliacartery 1 and across the stenotic lesion 3 can be achieved by repeatedlymoving back and forth the turbine 21 within the housing 23 of theadvancer mechanism 80. It should be noted that the back moving turbine21 pulls the elongated distal portion 14 of shaft 10, and the forwardmoving turbine 21 pushes on the proximal end of the elongated distalportion 14 of shaft 10. As it was already described, in the preferredembodiment of the invention, the guidewire is used only to advance thedrive shaft 10 through the iliac arteries. Pushing on the proximal endof the elongated drive shaft, after removing the guidewire, may causethe flexible drive shaft to bend within the elongated drive shaft sheath43. This, in turn, may cause discrepancy between the forward movement ofthe turbine 21 and the forward (proximal) movement of the abrasiveelement 16. An embodiment shown in FIGS. 7 trough 9 is addressing thisissue by providing a second advancer mechanisms 81 and moving theabrasive element 16 proximally across the treated stenotic lesion 3 bypulling the elongated proximal portion 11 of the drive shaft 10 by thesecond turbine 31 instead of pushing on the proximal end of theelongated distal portion 14 of the drive shaft 10 by the turbine 21. Thephysician is moving the abrasive element 16 in one direction across thestenotic lesion 3 by pulling the proximal end of the elongated portionof the drive shaft located on one side of the abrasive element 16, andthe physician is moving the abrasive element 16 in the oppositedirection by pulling on the elongated portion of the drive shaft locatedon the other side of the abrasive element 16. It should be noted thatthe second advancer mechanism 81 does not need to have a completeturbine assembly and the housing 31 may include only one or two bearingsfor rotatably supporting the proximal end of the shaft 10.

FIGS. 10 and 11 are side sectional views showing that proximal ends ofthe elongated distal and proximal portions and of the drive shaft 10(i.e. elongated portions located on the opposite sides of the abrasiveelement 16) can be connected to the opposite ends of the shaft of thesingle turbine 23′. This allows moving the abrasive element 16 back andforth across the stenotic lesion 3 by simultaneously pulling on oneelongated portion of the drive shaft and pushing on the other. The openarrows “A” in FIG. 11 indicate the direction of movement of the turbine23′ end the abrasive element 16. The turbine 23′ in FIG. 11 is pullingthe elongated proximal portion 11 of the drive shaft 10 andsimultaneously pushing on the elongated distal portion 14 of the driveshaft 10.

FIG. 12 is a side sectional view illustrating that after completing thetreatement of one iliac artery (i.e. right) the abrasive element 16 canbe repositioned into another iliac artery (i.e. left) without removingthe drive shaft 10 out of the patient's body.

FIG. 13 is a side sectional view illustrating chat one elongated portionof the drive shaft (i.e. distal portion 14) may extend out of thepatient through a first access opening located in the ipsilateralfemoral artery 9 of the patient and the other elongated portion of thedrive shaft (i.e. proximal portion 11) may extend out of the patientthrough a second access opening located in the radial artery 70 of thepatient instead of extending through the access opening in thecontralateral femoral artery 19.

It should be noted that radio opaque markers (rings) may be mounted tothe drive shaft sheaths in order to facilitate appropriate positioningof the sheaths within the treated iliac artery.

A preferred method of using the rotational (orbital) atherectomy deviceof the invention for treating a stenotic lesion in the iliac arteryshould include the following steps:

a) positioning the drive shaft in the iliac arteries such that oneelongated portion of the drive shaft extends out of the patient througha first access opening located in the femoral artery winch isipsilateral to the iliac artery to be treated, and the other elongatedportion of the drive shaft extends through a second access openinglocated in the femoral artery which is contralateral to the iliac arteryto be treated;

b) positioning the abrasive element within the stenotic lesion to betreated and locating the drive shaft sheaths in the treated iliac arterysuch that their distal ends are spaced away from the abrasive element;

c) inflating occlusion balloons of the distal sheaths;

d) initiating the flow of pressurized fluid through the first sheath anddraining it through the second sheath; and

e) initiating rotation of the drive shaft and repeatedly moving therotating abrasive element back and forth across the treated stenoticlesion;

f) deflating occlusion balloons, repositioning the abrasive element andthe drive shaft sheaths along the treated artery, and repeating thesteps b, c, d and e; and

g) if the other iliac artery also has a stenotic lesion, thenrepositioning the abrasive element in the other iliac artery,positioning the drive shaft sheaths in the treated artery such thattheir distal ends are spaced away from the abrasive element, andrepeating the steps b, c, d, e, and f.

While the present invention is described herein in terms of certainpreferred embodiments, those skilled in the art will recognize thatvarious modifications and improvements may be made to the inventionwithout departing from the scope thereof. Moreover, although individualfeatures of one embodiment of the invention may be discussed herein orshown in the drawings of the one embodiment and not in otherembodiments, it should be apparent that individual features of oneembodiment may be combined with one or more features of anotherembodiment or features from a plurality of the embodiments.

1. (canceled)
 2. A method of treating a stenotic lesion in an iliacartery of a patient, the method comprising: positioning a rotationalatherectomy device in the iliac artery, the rotational atherectomydevice comprising: a drive shaft that defines a longitudinal axis, thedrive shaft being flexible and rotatable, the drive shaft having anelongated proximal portion and an elongated distal portion; an abrasiveelement mounted to the drive shaft between the elongated proximal anddistal portions of the drive shaft and configured for rapid rotationtogether with the drive shaft, the abrasive element having a center ofmass that is eccentric from the longitudinal axis of the drive shaft; aproximal drive shaft centering element, the proximal drive shaftcentering element being coaxially disposed about the elongated proximalportion of the drive shaft and configured to center at least a portionof the elongated proximal portion of the drive shaft during rotation ofthe drive shaft; and a distal drive shaft centering element, the distaldrive shaft centering element being coaxially disposed about theelongated distal portion of the drive shaft and configured to center atleast a portion of the elongated distal portion of the drive shaftduring rotation of the drive shaft, wherein the elongated distal portionextends distally beyond a distal-most end of the distal drive shaftcentering element, wherein the drive shaft is positioned such that atleast the elongated proximal portion extends out of the patient througha first percutaneous access opening to a femoral artery that isipsilateral to the stenotic lesion in the iliac artery; rotating, by aprime mover coupled to the drive shaft, the drive shaft such that theabrasive element follows an orbit because of centrifugal force generatedby rotation of the abrasive element; and translating, by an advancermechanism coupled to the drive shaft, the abrasive element back andforth across the stenotic lesion.
 3. The method of claim 2, wherein therotational atherectomy device further comprises a pair of elongate driveshaft sheaths configured for slidably receiving the proximal portion ofthe drive shaft within one sheath and the distal portion of the driveshaft within the other sheath, the drive shaft sheaths having distalends and configured for extending around the drive shaft into thetreated iliac artery such that the distal ends of the sheaths arepositioned in the artery spaced away from the abrasive element, thespace between the distal ends of the drive shaft sheaths allowing therotating abrasive element to move back and forth across stenotic lesion.4. The method of claim 3, wherein the proximal drive shaft centeringelement is mounted to the distal end portion one of the drive shaftsheaths, and wherein the distal drive shaft centering element is mountedto the distal end portion of other of the drive shaft sheaths.
 5. Themethod of claim 4, wherein the proximal drive shaft centering elementand the distal drive shaft centering element are each balloon devices.6. A method of treating a stenotic lesion in an iliac artery of apatient, the method comprising: positioning a rotational atherectomydevice in the iliac artery, the rotational atherectomy devicecomprising: a drive shaft that defines a longitudinal axis, the driveshaft being flexible and rotatable, the drive shaft having an elongatedproximal portion and an elongated distal portion; an eccentric abrasiveelement mounted to the drive shaft between the elongated proximal anddistal portions of the drive shaft and configured for rapid rotationtogether with the drive shaft, the abrasive element having a center ofmass that is eccentric from the longitudinal axis of the drive shaft; atleast a first elongate drive shaft sheath having a lumen through whichthe drive shaft extends toward the iliac artery and being configured toremain stationary while the drive shaft rotates; and a distal stabilityelement being positioned coaxially with the elongated distal portion ofthe drive shaft and configured to provide stability to the elongateddistal portion of the drive shaft while the drive shaft rotates, whereinthe elongated distal portion of the drive shaft extends distally beyonda distal-most end of the distal stability element, wherein the driveshaft is positioned such that at least the elongated proximal portionextends out of the patient through a first percutaneous access openingto a femoral artery that is ipsilateral to the stenotic lesion in theiliac artery; rotating, by a prime mover coupled to the drive shaft, thedrive shaft such that the eccentric abrasive element follows an orbitbecause of centrifugal force generated by rotation of the eccentricabrasive element; and translating, by an advancer mechanism coupled tothe drive shaft, the eccentric abrasive element back and forth acrossthe stenotic lesion during the orbit of the eccentric abrasive element.7. The method of claim 6, wherein the rotational atherectomy device inthe iliac artery further comprises a proximal balloon element mounted ona distal end of the first elongate drive shaft sheath and configured toabut with an artery wall so as to provide stability to the elongatedproximal portion of the drive shaft while the drive shaft rotates. 8.The method of claim 7, wherein the proximal balloon element comprises anocclusion balloon configured to restrict the flow of fluid around aperimeter of the first elongate drive shaft sheath.
 9. The method ofclaim 6, wherein the distal stability element comprises a distal balloonelement mounted on a distal end of a second elongate drive shaft sheathand configured to abut with the artery wall so as to provide stabilityto the elongated distal portion of the drive shaft while the drive shaftrotates.
 10. The method of claim 9, wherein the distal balloon elementcomprises an occlusion balloon configured to restrict the flow of fluidaround a perimeter of the second elongate drive shaft sheath.
 11. Themethod of claim 6, further comprising a source of pressurized fluid forsupplying a fluid through the first drive shaft sheath and toward theeccentric abrasive element.
 12. The method of claim 6, wherein theelongated distal portion of the drive shaft extends at least 15 cmdistally beyond a distal-most end of the distal stability element. 13.The method of claim 6, wherein said positioning a rotational atherectomydevice in the iliac artery comprises advancing the drive shaft over aguidewire, the method further comprising withdrawing the guidewire fromthe drive shaft after advancing the drive shaft over the guidewire. 14.The method of claim 6, wherein the rotational atherectomy devicecomprises the first elongate drive shaft sheath and a second elongatedrive shaft sheath, the first elongate drive shaft sheath beingconfigured for slidably receiving the proximal portion of the driveshaft and the second elongate drive shaft sheath being configured forslidably receiving the distal portion of the drive shaft within theother sheath, the first and second drive shaft sheaths having distalends and configured for extending around the drive shaft into thetreated iliac artery such that the distal ends of the sheaths arepositioned in the artery spaced away from the eccentric abrasiveelement, the space between the distal ends of the drive shaft sheathsallowing the rotating abrasive element to move back and forth acrossstenotic lesion.
 15. The method of claim 14, further comprising a sourceof pressurized fluid for supplying a fluid through the first drive shaftsheath and aspirating the fluid and abraded particles through the seconddrive shaft sheath.
 16. The method of claim 6, wherein a secondpercutaneous access opening is located in a femoral artery which iscontralateral with respect to the iliac artery, and wherein theelongated distal portion of the distal drive shaft extends out of thepatient through the second percutaneous access opening.
 17. The methodof claim 6, wherein a second percutaneous access opening is located inan artery of the upper extremity of the patient, and wherein theelongated distal portion of the distal drive shaft extends out of thepatient through the second percutaneous access opening.
 18. The methodof claim 6, wherein during the rotating of the drive shaft the distalstability element causes at least a portion of the elongated distalportion of the drive shaft to be positioned generally centrally withinthe iliac artery.
 19. The method of claim 6, wherein the drive shaft isconfigured to extend throughout an entire length of the iliac artery.